Our brains are littered with passwords and alphanumeric combinations that span all levels of necessary corporate and personal security-from bank accounts and PINs, to work-related e-mail and network log-ons, to e-commerce and social networking sites.

A neurological researcher who is fully appreciative of the dizzying increase in passwords and other things to memorize, however, argues that we all can remember much more if we practice visualizing the information we want to recall.

But first: What should we actually try to commit to memory these days? It seems like a legitimate question. (Personally, here's how many computer-related passwords I can remember off the top of my head: three. I figure I have a total of 50 or so passwords which I need to recall during a typical month.)

Recent research from Ian Robertson, professor of psychology at the Institute of Neuroscience and School of Psychology at Trinity College in Dublin, Ireland, illustrates the growing amount of alphanumeric clutter in our heads: the average person now has to remember five passwords, five PIN numbers, two number plates, three security ID numbers and three bank account numbers just to get through everyday life.

A 2007 study of Web users by Microsoft Research found that the average user has 6.5 Web passwords, each of which is shared across almost four different websites. In addition, each user has about 25 accounts that require passwords, and types an average of 8 passwords per day.

Too Much To Remember?

Not surprisingly, Robertson's research found that nearly 60 percent of those studied felt like they couldn't possibly remember all of these numbers and letters that they were supposed to. A consequence of this "information overload" was that most users today create weak passwords (dog's or child's name usually top the list) or rely heavily on technology to create or store of the alphanumeric data.

To which Robertson responds: "People are incapable [of remembering passwords] because of the particular ways they have been taught to remember," he says. "We can use our brains much more than we do. And if we could be bothered, we could happily remember two dozen passwords using some fairly standard memory methods."

Flexing the Brain's Memory Muscles

The brain is just like any other part of our body when it comes to use, Robertson contends: "Use it or lose it." His recent study showed the generational differences and how the brain can seemingly atrophy. In Robertson's survey, for example, almost a third of those under 30 couldn't remember their home telephone number, which was usually stored on their mobile device or on a piece of paper.

"I was astonished that a significant percentage of people didn't know their own cell phone number or landline number without looking it up," Robertson says. "And this was much more so of younger people, who are reliant on technology, and that's leading to the underuse of certain areas of the brain." (A recent article in The Atlantic, by Nicholas Carr, asked if Google was making us stupid-was the Internet negatively influencing our brain's processing abilities, especially in how we read?)

The under-30 generation fared even worse with important dates, such the birthdays of close family members: 87 percent over 50 could remember the details, compared with just 40 percent of those under 30.

Other research proves the idea that the brain needs to be "exercised" to make it stronger. In 2007, Stanford University researchers discovered that "the brain's ability to suppress irrelevant memories makes it easier for humans to remember what's really important," notes a Stanford News Service article. For example, passwords that have to be changed every six months are an opportunity to forget an old one and remember a new one.

"The extent to which these brain mechanisms weaken the old password, then they don't have to be used as much in future attempts to remember the new one," says Anthony Wagner, a professor in Stanford's psychology department. "From a neural standpoint, forgetting the old password makes the brain more efficient